Today, I found that
the main server, tistory.com, makes a strage respond to English replies and guestbooks.If you write only English there,
the server considers it as a spam message and block it.I was quite shocked of this happening.
You must have been displeased when it happend. Sorry for your inconvenience.

Solution

You need to write at least one word in Korean
to successfully comment on my post.It can be your name in Korean or any meaningless word(ex.하하, 호호, 랄라) in Korean.Any Korean word is acceptable. Thank you for your kind understanding.